Aminoarylazopyridine oxide dyeing nickel modified polypropylene fibers and fibers so dyed

ABSTRACT

Nickel-containing polypropylene fibers and fabrics are dyed with azo dyes conforming to the formula: WHEREIN Ar is an aryl radical containing a hydroxy group positioned ortho to the point of azo attachment and which may be further substituted with an amino, alkyl, alkylamino or dialkylamino group. A preferred dye is 2-hydroxy-1naphthylazopyridine-1-oxide.

United States Patent Inventor Charles Edward Lewis Somerville, NJ.

Appl. No. 888,921

Filed Dec. 29, 1969 Patented Nov. 2, 1971 Assignee American CyanamidCompany Stamlord, Conn.

AMINOARYLAZOPYRIDINE OXIDE DYEING NICKEL MODIFIED POLYPROPYLENE FIBERSAND FIBERS S0 DYED 8 Claims, No Drawings 11.8. CI 8/42 D, 260/ l 55 Int.Cl D06]: 3/00 Field of Search 260/155;

[56] References Cited UNITED STATES PATENTS 3,393,190 7/1968 Stright8/42 Primary Examiner-Donald Levy Anarney.lohn L. Sullivan ABSTRACT:Nickel-containing polypropylene fibers and fabrics are dyed with azodyes conforming to the formula:

AMINOARYLAZOPYRIDINE OXIDE DYEING NICKEL MODIFIED POLYPROPYLENE FIBERSAND FIBERS SO DYED The present invention relates to polypropylenedyeing. 5

More particularly, it relates to an improved process for dyeingnickel-containing polypropylene fibers and fabrics utilizing a definedclass of pyridine N-oxide azo dyes.

Polypropylene used for fibers and fabrics contains a variety ofstabilizers to protect it from the damaging effects of heat and light.Among the light stabilizers frequently used are diverse nickelcompounds, such as nickel salts of organic acids, nickel alcoholates andnickel chelates. Illustrative of such compounds are nickel acetate,nickel stearate, nickel alkoxides and nickel chelated withbis-(p-alkylphenol)monosulfide, 8-hydroxyquinoline, salicylaldoxime oro-hydroxybenzoacetophenone. The nickel stabilizers are present instabilized polypropylene in amounts of from about 0.1 percent to about10 percent, by weight, and usually from about 0.05 percent to about 1.0percent.

ln the past, these nickel-containing polypropylene fibers and fabricshave presented dyeing problems in that the dyes heretofore used havelacked sufficient affinity for the fibers whereby the dyed fibers lackedgood lightfastness and resistance to dry cleaning, crocking and gasfading. There is, therefore, a need for dyes which exhibit good affinityfor the fiber whereby these dyeing deficiencies are overcome. It is theobject of the present invention to provide such dyes.

This object has been accomplished by the present invention whereby ithas been found that certain pyridine N-oxide azo dyes exhibit excellentaffinity for polypropylene fibers containing covalently held nickel.

The dyes of the invention conform to the formula:

wherein Ar is an aryl moiety having a hydroxyl group positioned ortho tothe point of azo attachment and which is otherwise unsubstituted orsubstituted with a group selected from an amino group, an alkyl group ofl-4 carbon atoms, an alkylamino group of l-4 carbon atoms and adialkylamino group in which each alkyl group contains l-4 carbon atoms.

Representative of these dyes are: ynaphthylazopyridinel -oxide,2-hydroxy5-methyll naphthylazopyridine-l-oxide which are preferred aswell as 2- hydroxy-S-dimethylaminonaphthyl azopyridine-l-oxide and2-hydroxy-8-aminoaphthylazopyridine-l-oxide.

The dyes of the invention are readily prepared by coupling a diazotizedZ-aminopyridine-l-oxide with an appropriate aryl compound in a suitablesolvent, such as acetone, water or dimethylformamide. These dyes arecharacterized as one to 'four affinity for the nickel-containingpolypropylene fiber one to four while at the same time exhibitingsuperior fastness to light, dry cleaning, one to four gas-fading.

The dyeing process is effected in an acid bath containing an inorganicor organic acid, such as sulfuric acid, phosphoric acid, sulfamic acid,formic acid or acetic acid, at a pH of about '2 to about 6 and,preferably, at a pH of about 3-4. Acetic acid is the acid of choicesince it conveniently provides a pH of 3.5. The'temperature may rangefrom about 180 F. to about 212 F., a range from about 200 F. to about205 F. being preferred, since, at boiling, the dye adheres too rapidly.

To facilitate the dyeing process, an anionic or nonionic surfactant maybe added to the acid medium in amounts ranging from about 1 to 2percent, based on the weight of dyestuff. Typical of such surfactantsare sodium di(2-ethylhex- 2-hydrox- 1 yl)phosphate, sodium laurylsulfate and nonylphenoxypoly(ethyleneoxy)ethanol.

The following examples will serve to further illustrate the invention.These are not to be taken as limitative. All parts are by weight unlessotherwise stated.

EXAMPLE 1 Dyeing with Z-Hydroxyl -naphthylazopyridinel -oxide Procedure:To 5 parts (by volume) of acetone are added 0.025 part of a dye of theabove formula prepared by coupling diazotized 2-aminopyridinel -oxide to2-naphthol. The resulting acetone solution is poured into 100 parts ofwater containing 1 part (by volume) of a 5 percent solution of anonionic surfactant, which is a mixture of polyoxyethylene ether alcoholplus urea. The volume of the bath is brought to 200 parts (by volume)with water. To itis added 1 part (by volume) of a 5 percent solution of56 percent sulfuric acid.

A 5-part sample of knit nickel-polypropylene fabric containing 0.05percent nickel, is entered. The whole is heated to 200 F. and held at200 F. for 1 hour.

The fabric dyes' in 0.5 percent shade, is removed and scoured in boilingsoap solution in which it shows nov bleeding or shade change. It is dyeda violet due of good color value and excellent fastness.

Lightfastness rating is 6, corresponding to hours stability to light ina carbon-arc FadeOmeter. A top rating fastness of 5 is obtained for drycleaning test No. 85, for wet crocking and for gas-fading 3 cycles).Tests and rating scales are standard and given in the AATCC TechnicalManual, Section 2, Colorfastness.

EXAMPLE 2 Dyeing with Z-Hydroxy-S-methyll -phenylazopyridinel oxideProcedure: To 5 parts (by volume) of acetone is added 0.025 part dye ofthe above formula prepared by coupling diazotized2-aminopyridine-l-oxide to cresol and recrystallisingfrommethylcyclohexane. Two parts (by volume) of a 2% percent solution ofsodium dodecylbenzenesulfonate, an anionic agent, is added. The whole isdiluted with200 parts of water. To the bath is added 2 parts of a 5percent solution of 28 percent acetic acid. A S-part sample of knitnickelpolypropylene containing 0.05 percent nickel is entered. Thenickel-polypropylene is dyed at 205 F. for 1 hour.

The dyes polypropylene is removed, rinsed and scoured as in example 1.It shows no bleeding with this treatment.

The polypropylene is dyed in 0.5 percent shade a navy blue of good colorvalue. AATCC fastness tests on the dyed fiber show it tohave alightfastness rating of 4-5, dry cleaning 5, wet and dry crocking 4-5,and gas fading 4-5 after 3 cycles.

EXAMPLE 3 This example illustrates dyeingwithout the use of asurfactant.

Procedure: A 0.025 part sample ofthe dye of example 2 is dissolved in200 parts of water to form a-clear orange solution.

EXAMPLE 4 Dyeing with 2-Hydroxy-5-dimethylaminophenylazopyridine-l-oxide Procedure: When a dye of the above formula prepared by couplingdiazotized 2-aminopyridine-l-oxide to mdimethylaminophenol is dyed onnickel-polypropylene using the method of example 3, a red-brown ofmedium depth is obtained in 0.5 percent shade.

EXAMPLE 5 Dyeing with 2-Hydroxy-8-amino-l -naphthylazopyridine-1- oxideProcedure: A 0.025 part sample of a dyestuff of the above formula,prepared by coupling diazotized Z-aminopyridine-loxide to8-amino-2-naphthol in dimethylformamide solvent, is dispersed in 200parts of water by the addition of 5 parts (by volume) of a 5 percentsolution of the nonionic agent nonylphenoxypoly(ehtyleneoxy)ethanol. Tothe bath is added 2 parts (by volume) ofa 5 percent solution of 28percent acetic acid. A S-gram skein of nickel polypropylene containing0.05 percent nickel, is entered and the whole heated for 1 hour at 205F.

The dyed skein is removed from the bath, rinsed, scoured and dried. The0.5 percent shade is a chocolate brown of medium depth.

Lightfastness rating is 5, dry cleaning (Test No. 85) is b 5, crockirig45, and gas-fading 4-5. 7

If 8-amino-2-naphthol is replaced by 8-methylamino-2- naphthol, theresulting dye provides a similar dyeing result.

Tests and ratings in the examples are standard and described in theAATCC Technical Manual, Section 2, Colorfastness.

Iclaim:

l. A process for dyeing nickel-containing polypropylene fibers andfabrics which comprises contacting the fiber or fabric with a compoundof the formula:

wherein Ar is an aryl moiety having a hydroxyl group positioned ortho tothe point of azo attachment and which is substituted with a groupselected from an amino group, an alkylamino group of one to four carbonatoms and a dialkylamino group in which each alkyl group contains one tofour carbon atoms; in an aqueous bath having a pH of from 2 to 6 whilemaintaining the temperature of the bath at l-2 1 2 F.

2. The process of claim 1 wherein the compound is 2-hydroxy-S-dimethylaminophenylazopyridine-l-oxide.

3. The process of claim 1 wherein the compound is 2-hydroxy-B-amino-l-naphthylazopyridine-l-oxide.

4. The process ofclaim 1 wherein the pH is 3-4.

5. The process of claim 1 wherein the temperature of the bath is 200-205F.

6. The dyed product ofclaim 1.

7. The dyed product ofclaim 2.

8. The dyed product of claim 3.

2. The process of claim 1 wherein the compound is2-hydroxy-5-dimethylaminophenylazopyridine-1-oxide.
 3. The process ofclaim 1 wherein the compound is2-hydroxy-8-amino-1-naphthylazopyridine-1-oxide.
 4. The process of claim1 wherein the pH is 3-4.
 5. The process of claim 1 wherein thetemperature of the bath is 200*-205* F.
 6. The dyed product of claim 1.7. The dyed product of claim
 2. 8. The dyed product of claim 3.